Improvement in spring motive powers



T. B. FD GARTY.

Sp ri ng Mtve-Powers.

Patented an. 7, 1873.

rrHoMAs BURKE noennrv, or New YORK, N. Y.

IMPROVEMENT IN SPRING MOTIVE POWERS.

Specification forming part of Letters Patent No. 1341,633, dated January 7, 1873.

To all whom it may concern:

Be it known that I, THOMAS BURKE Fo- GARTY, of New York, in the county and State of New York, have invented certain new and useful Improvements in Spring Motive Powers, of which the following is a specification:

Natnre .and Objects of the Intention.

The said invention relates tothe use of one or more springs as a driving-power for sewing-machines and other small machinery; and it has for its object the restraint ofthe tensile l'orce of the spring or springs when at its greatest tension, and its continuous and pro` portionate reduction in such a manner that the working force will be uniform within practical limits for the operation of a machine at a nearly-uniforn1 speed. To accomplish this purpose the invention consists in combining two .springs or systems of springs that are similar in their rate of variation, although the one which may be termed the regulating- -spring may have much less strength than the other, in such a way that the tension of the regulating-spring or springs acts as alcheck upon the motor-sprin g or springs, and continues to act with proportionately-diminished force as the power ot' the latter is gradually expended.

Description of the Dra/wing.

shaft of one of which, and preferably of the last, is attached a brake-wheel, c, which has a smooth periphery, and mayllave its upper edge made as a crown or miter wheel,t'ro1n which the power may be taken to drive the machinery thatit is desired to operate. The

outer end or case of the small or regulating* spring cl has an arm, f, which bears upon the arm or lever g that operates the brake-block h, and causes itto bear against'the periphery of the wheel e. When the large spring is wound up the small one is also wound by the same operation, and the tension ot' the smaller spring acting through the brake, restrains the force of the larger one. The restraining force may be regulated by the position of the movable nipple t', and also by securing the inner end ot' the small spring toa collar or sleeve, the position of which may be adjusted on the shaft by a set-screw. rlhe machine may be wound up by any ot' the means for such purposes known to mechanics. A convenient method consists of a pinion gearing into the teeth ofthe springcase or barrel b, and on the same shaft k with a ratchet-wheel and a loose wheel, through which the power should be transmitted. A brake, l, for the purpose of arrest-ing the machine at the pleasure of the operator, may be attached in such a manner that it will be brought to bear upon some one ot' the train of wheels to stop the machine by the action of a spring which may be controlled by a handle or a treadle.

Different forms of springs may be used, and the details ot' construction and arrangement may be otherwise varied without departure from the essential feature ot' the invention, consisting in the relation to each other ofthe driving and regulating springs.

Claim.

scribed.

'IHOS. B. FOGARTY.

Witnesses:

WM. KEMBLE HALL, NATHAN LEWIS. 

